SU758528A1 - Frequency synthesizer - Google Patents

Description

(54) FREQUENCY SYNTHESIZER

one

The invention relates to radio engineering and can be used as a frequency synthesizer in transmitting and receiving and measuring devices.

A device comprising a mixer and a frequency detector, forming a difference frequency selection unit, a reverse trigger and a pulse counter, forming a reversible counter, and a digital-to-analog converter 1 are known.

However, such a device has false output frequencies.

The closest technical solution to this invention is a frequency synthesizer comprising a ring-controlled control oscillator, a first mixer, a variable frequency divider, a phase detector and a low-pass filter, as well as a series-connected frequency generator, a frequency divider with a fixed coefficient division and a harmonic generator, one of the outputs of which is connected to another input of the first mixer, the second output of a frequency divider with a fixed division factor with united with the other phase input

the detector and one of the inputs of the device auto search 2.

However, in this frequency synthesizer also

False output frequencies are not excluded.

The purpose of the invention is the elimination of the formation of false output frequencies.

This is achieved by the fact that in a frequency synthesizer comprising a controllable oscillator connected in a ring, a first mixer, a variable division frequency divider, a phase detector and a filter

Claims (2)

1. USSR author's certificate number 531244, cl. H 03 B 3/04, 01/03/1975. 2.Zaretsky M.M. and Movshovich M.E. Frequency synthesizers with a phase self-tuning ring. L., “Energie, 1974, p. 207210, 249-250 (prototype).